Losing Illustrator Clipping Mask

I have an odd thing happening with one particular file, on the same graphic repeatedly. I have been using Illustrator for 20 years and used to teach it to an advanced level. I am experienced. But I can't seem to figure out what's going on.

I have an icon that I created. It's circular and has a magnified tape measure inside it. The graphic looks like the tape measure is folded over and is showing that both sides of the tape measure have measurements on them. All items are vector and the set of elements making up the icon have been clipped to a circle.

Every single time I close and open the file the icon has unclipped itself. The circle that's being used to clip the elements is still there but it's as if the unclipping mask has been released.

This wouldn't be a big deal if it was only one file but this is being turned into a long SKU list of files. I want to solve what it might be so it doesn't happen every time all of the SKUs are closed and reopened.

Any one had something like this happen? Or know how I can fix it?

Thanks!